Mower blade and connection therefor

ABSTRACT

A connection for attaching a mower blade directly to a lug provided on a mower shaft. The blade comprises a pair of resilient fingers cooperating with an opening provided in the lug. The opening in the lug may be circular or non-circular having a long and a short dimension. The long dimension of the non-circular opening is such that when the blade is turned to the long dimension and the fingers are compressed, the fingers will pass through the opening. The short dimension is such that when the blade is turned to such short dimension, the blade cannot be compressed sufficiently to be removed from the opening of the lug. The blade may be removed from the circular opening, regardless of the position of the blade in the opening, by compressing the blade. To connect the blade to the lug of the shaft, the fingers of the blade are gripped in a tool and compressed, and the compressed fingers are then inserted into the opening in the lug. Notches provided in the edges of the fingers are aligned with the margin of the opening in the lug, and the fingers are then released so that the notches loosely engage the lug to retain the blade on the lug. By a converse operation the blade may be removed from the lug.

[ 51 July 25,1972

626,954 9/1961 Canada........... Great Britain..........................

[54] MOWER BLADE AND CONNECTION THEREFOR Primary Examiner--Russell R.Kinsey Attorney-Hibben, Noyes & Bicknell [72] Inventor: Carl W. Mott,Lake Ozark, Mo.

[73] Assignee: Mott Corporation, LaGrange, Ill.

[22] Filed: Sept. 25, 1970 ABSTRACT A connection for attaching a mowerblade directly to a lug [21] Appl. No.: 75,347

provided on a mower shaft. The blade comprises a pair of resilientfingers cooperating with an opening provided in the Related U.S.Application Data [63] Continuation-impart of Ser. No. 54,246, July 13,

lug. The opening in the lug may be circular or non-circular 1970,abandone having a long and a short dimension. The long dimension of thenon-circular opening is such that when the blade is turned 52 U S C] 1to the long dimension and the fingers are compressed, the fing will pthrough the p g The short dimension is such that when the blade isturned to such short dimension,

[51] Int. Cl. [58] Field of the blade cannot be compressed sufficientlyto be removed from the opening of the lug. The blade may be removed fromReferences Cited the circular opening, regardless of the position of theblade in UNITED STATES PATENTS the opening, by compressing the blade. Toconnect the blade to the lug of the shaft, the fingers of the blade aregripped in a tool and compressed, and the compressed fingers are theninserted into the opening in the lug. Notches provided in the edges ofthe fingers are aligned with the margin of the opening 56/294 in thelug, and the fingers are then released so that the notches looselyengage the lug to retain the blade on the lug. By a converse operationthe blade may be removed from the lug.

em n m da eh mkn MBRF 0689 7656 9999 1111 l/l/ 47 9 0 57 0570 3 5 050666 3323 FOREIGN PATENTS OR APPLlCATlONS 1,127,515 9/1968 GreatBritain...........................56/294 17 Claims, 9 Drawing FiguresPatented July 25, 1972 3,678,668

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MOWER BLADE AND CONNECTION THEREFOR CROSS REFERENCE TO RELATED CASE Thisapplication is a continuation-in-part of my copending U.S. applicationSer. No. 54,246 now abandoned, filed July 13, 1970.

This invention relates to mowers, and more particularly to a novel bladeconnection for directly attaching a blade to a mower.

The present invention relates to a mower of the type shown in my priorU.S. Pat. No. 2,71 1,067 issued June 21, 2955, and includes a horizontalrotatably driven shaft extending transversely of the direction oftravel. Mounted on the shaft are a plurality of axially spaced lugsextending radially therefrom, to which are loosely secured a pluralityof blades or knives, the latter being adapted toextend outwardly fromthe lugs by virtue of centrifugal force.

Heretofore, blades for mowers of the type described were attached orsecured to the lugs by intermediate fasteners or clips. Although suchblade connections worked satisfactorily, additional parts were needed toconnect the blades to the lugs.

The present invention has eliminated the need for such additional partsby directly connecting the blade member to the lug member of the mowershaft. To this end, a resilient elastic connecting means is provided onthe members to connect the blade to the lug. The blade may be quicklyand easily installed, or disconnected, from the lug by deforming theresilient connecting means and removing the blade from the lug.

Accordingly, it is the general object of the present invention toprovide an improved construction for connecting a blade to a lug of amower shaft which is simple and inexpensive to manufacture.

Other objects and advantages of the invention will become apparent fromthe following description and accompanying drawings in which:

FIG. I is a fragmentary front elevational view of a mower shaftincorporating a first embodiment of the present inventron;

FIG. 2 is an enlarged cross-sectional view taken on the line 2-2 of FIG.1;

FIG. 3 is a perspective view of a portion of the shaft shown in FIG. Iand a blade being connected to the lug;

FIG. 4 is a perspective view of the blade of the first embodiment;

FIG. 5 is a fragmentary perspective view of an alternate bladeconstruction;

FIG. 6 is an enlarged cross-sectional view of the rotating parts of amower, having an alternative lug construction;

FIG. 7 is a cross-sectional view taken on the line 77 of FIG. 6;

FIG. 8 is a cross-sectional view taken on the line 88 of FIG. 6; and

FIG. 9 is a cross-sectional view taken on the line 99 of FIG. 6.

In FIG. I, a horizontal shaft, indicated at 10, of a mower of the typewith which the blade connection of the present invention is to be used,is illustrated. The ends of the shaft 10 are in a housing (not shown)having bearing structure ll for supporting the shaft. When the mower isin use, the shaft 10 is rotated about its axis, as for example by apulley and belt arrangement connected to an engine.

The shaft 10 is preferably non-circular, in this instance square incross section and of a length depending on the mower size.

On the shaft 10 at spaced intervals are located lug members 12 to whichblade members 14 are directly connected. While the lugs may be securedintegrally to the shaft as by welding, the lugs 12 are preferablyremovably secured to the shaft to accommodate different sized blades andto facilitate replacement of damaged or worn lugs 12. The lugs 12constitute the opposite end portions of a flat elongated strip I6 havingat its center a square opening 18 to accommodate the square shaft I0.The adjacent strips 16 are displaced 90 apart. Each strip 16 may be slidinto position on the shaft 10 and is axially spaced from adjacent strips16 by tubular spacers 20 which are also slidable onto the shaft 10. Thespacers 20 abut the strip 16 to locate the lugs 12 along the shaft. Thespacers and lugs are held in abutment on the shaft by means located atthe ends of the shaft. In the present instance, the spacer at one end ofthe shafl abuts a bearing 11 in the housing supporting the shaft, and atthe other end, spring means in the form of a coil spring 21 is mountedon the shaft between the bearing 11 at that end of the shaft and the endstrip 16.

At the outer ends of the lug members 12, and on the blade members 14 arelocated co-operating connecting means. The co-operating connecting meanscomprises resilient means one one of said members, and an openingprovided in the other of said members to receive said resilient means.While the resilient means can be on the lug member and the openingprovided in the blade member, in this instance, the co-operatingconnecting means comprises a circular opening 24 in the other end of thelug and resilient fingers formed on the blade 14. Each blade 14comprises an elongated member having cutting edges and resilient fingersto connect the blade to the lug. As is shown in FIG. 4 the blade isformed from a metal strip and has a center portion 28 and two bent ends30 and 32. One end 30 of the blade 14 is sharpened so as to provide twocutting edges 26 and 27. Should one edge, for example edge 26, becomeworn the other edge 27 may be used by reversing a blade 14 on itsassociated lug 12, as is shown in dashed lines in FIG. 1. When a bladeis reversed in this manner, the blade on the opposite lug should also bereversed so that the swath cut by the respective blades will be completeand the dynamic balance maintained End 30 of the blade 14 is bent withrespect to the center portion 28 of the blade generally at differentangles depending on the length of the blade. The other end 32 of theblade, which is connected to the lug 12, is also bent with respect tothe center portion 28 at an angle which will shed cuttings when rotatedat high speed. Different length blades would require different anglesbetween the bent end 32 and center portion 28 thereof in order to assureshedding of cuttings.

While the resilient fingers could have been provided on the lug, in thisinstance the resilient fingers 34 are formed on the blade by bifurcatingthe latter. The blade 14 is made of tempered steel, and the fingers 34may be compressed until their ends abut and will upon release return totheir normal position. The fingers 34 are formed by cutting a slot 36into the end 32 of the blade 14. In this instance, the slot 36 has beencarried down into the center portion 28 to permit each finger 34 todistort by twisting and to decrease the force necessary to compress thefingers. As is shown in FIG. 4, the inner end of the slot 36 is roundedto reduce the stress concentration at that point. The outer edges 42 ofthe fingers 34 are parallel and have a width greater than the diameterof the opening 24 so that the end 32 of the blade 14 when uncompressedwill not pass through the opening 24. The outer edges of the blade 14,having notches 43 therein, may be brought toward each other bycompressing the fingers 34 with a tool, preferably in the form of apliers 44 shown in FIG. 3. The pliers 44 have jaws 46 and 48 connectedto handles 50 and 52 such that squeezing the handles 50 and 52 will movethe jaws 46 and 48 toward each other to compress the fingers 34together. A conventional pliers could also be used to compress thefingers 34.

The blade 14 may be installed in the lug 12 by the following operations:the fingers 34 of the blade 14 are compressed until the end 32 of theblade can pass through the opening 24. Depending on the width and shapeof the blade I4 it may be necessary to first cock the blade so that oneof the notches 43 first engages one side of the opening 24. Tips 54 onthe fingers 34, which help align the end 32 of the blade with theopening 24, may then be inserted into the opening 24 until the notches43 are adjacent the margin 58 of the lug 12. If conventional pliers areused, the tips 54 of the fingers 34 are first inserted through theopening 24 and then the tips may be gripped with the pliers to compressthe fingers. The fingers 34 are then shifted through the opening 24until the notches 43 are aligned with the margin 58 of the opening 24.The pliers are then released and the fingers 34 spring back so that thenotches 43 engage the margin 58 of the opening 24. The blade may beremoved from the lug by reversing these operations. With the circularopening 24 the blade may be installed or removed from the openingregardless of the position of the end 32 of the blade in the opening.

In the form of blade, indicated at 60, shown in FIG. 5, the outer end ofthe blade is bent and sharpened in the same manner as the end 30 of theblade 14. The inner end, indicated at 61, of the blade 60 is alsosimilar to the inner end of the blade 14 and is provided with a slot 66terminating in the central portion, indicated at 62, of the blade anddefining a pair of fingers 67. The fingers 67 thus extend from the innerend 61 into the central portion 62 of the blade 60. A pair of notches 68are formed in the outer margins of the fingers 67 for engaging themargin 58 of an opening 24 in the lug 12.

- The blade 60 differs from the blade 14 in that the tips 54 of theblade 14 are omitted from the fingers 67 of the blade 60. Suchconstruction facilitates shifting of the fingers 67 into and out of theopening 24 in the lug and results in a more economical construction inthat the total length of the blade 60 is shortened. To this end, theouter ends, indicated at 69, of the fingers 67 are curved.

A pair of either form of blade when mounted on the lugs 12 on each strip16 is in dynamic balance. The lugs 12 on each strip 16 are located inthe same plane and are transverse to the axis of the shaft 10. Theblades are relatively movable with respect to the lugs 12 in a planeincluding the axis of the shaft so that upon rotation of the shaft thecenters of gravity of the blades are positioned to dynamically balancethe blades. The width of the notches is such as to permit theabove-mentioned movement.

The blades are also free to move in a plane transverse to the axis ofthe shaft so that the blades will pivot on the lug in such plane shouldthe blades strike a rock or similar object.

The form of lug, indicated at 70 in FIGS. 6 through 9 is the same as thelug 12, except for the opening therein hereinafter described. Thus, thelugs 70 constitute the opposite end portions of a flat, elongated strip65 which is secured to a mower shaft 71 in the same manner as the strip16 of the previous embodiment, and a blade, in this instance the blade60 previously described, is connected to each lug 70. An opening 72 isprovided at the outer end of each lug 70 for receiving and retaining ablade 60.

Each opening 72 is non-circular to facilitate installation of a bladeand to improve retention of the blade. Preferably, the opening 72 ispear-shaped and has long and short dimensions, respectively indicated at73 and 74 in the opening 72 in the upper lug 70 in FIG. 6. Each opening72 is arranged in the lug 70 so that the long dimension 73 thereof liessubstantially on or parallel to a shaft radius with the short dimension74 transverse to the long dimension 73. In addition, each opening 72 isarranged so that the short dimension 74 thereof is positioned closer tothe radially outer end of the long dimension 73 than to the radiallyinner end of the long dimension.

The procedure for installing a blade in an opening 72 is generallysimilar to that previously described. Thus, as shown in FIGS. 6 and 7,the connecting means or fingers 67 of the blade 60 lie in a plane andare compressed as by the jaws of a pair of pliers 44, thus reducing thewidth of the inner end 61 of the blade. The blade 60 is then cockedturned or slightly so that the plane of the connecting means is alignedwith the long dimension, as shown in FIGS. 6 and 7, and the blade 60 isthen inserted at the long dimension of the opening 72 with one of thenotches 68 engaging the margin of the opening 72 at its long dimension.The blade is then straightened in the opening 72 and is released fromthe pliers, both notches 68 then engaging the margin of the opening 72.The long dimension may be slightly shorter than the width of the bladewhen uncompressed so that the blade will still be retained even at thelong dimension of the opening 72 when the blade is released.

During operation of the mower, rotation of the shaft and centrifugalforce will cause the blades to extend in a generally radial direction.The inner end 61 of each blade 60, in this instance, will rotate to aposition which generally coincides with the short dimension of theopening 72. The blade contacts the margin of the opening 72 adjacent theshort dimension which is preferably slightly larger than the width ofthe blade between the bottoms of the notches 68. Thus, the blade is freeto pivot in the opening 72. Since the short dimension of the opening 72is less than the width of the end 61 of the blade when compressed, theblade cannot become disconnected even if it should strike a solid objectwhile rotating and be compressed. Should the blade turn in the openingto the long dimension, the blade will still be retained on the lug sincethe fingers of the blade have to be compressed to remove the blade.

It is apparent that a novel blade connection for a mower shaft havinglugs has been provided wherein the blades have resilient connectingmeans to connect the blade to the lug of the shaft.

1 claim:

1. ln a mower having a shaft, the combination of a lug member adapted tobe secured to said shaft and extending generally radially therefrom, anda blade member, one of said members having means resilientlydisplaceable for removably engaging with the other of said members toconnect said members.

2. The combination of claim 1, wherein said resiliently displaceablemeans comprises a pair of fingers on one of said members, the other ofsaid members having an opening to removably receive said fingers.

3. The combination of claim 2, wherein said opening is noncircular andhas a long and a short dimension, said short dimension being transverseto a radius of said shaft, and said long dimension being generallyparallel to said radius.

4. The combination of claim 3, wherein said opening is pear-shaped.

5. The combination of claim 2, wherein said fingers are formed on saidblade, and said opening is formed in said lug.

6. The combination of claim 2, wherein at least one of said fingers hasa notch for engaging the margin of said opening.

7. The combination of claim 2, wherein said opening is smaller than thewidth of said fingers when in their normal position, said fingers beingcompressible toward each other for insertion into said opening, each ofsaid fingers having a notch in its outer edge for engaging the margin ofsaid opening when said fingers are inserted in said opening and arereleased from compression.

8. A mower blade adapted to be connected to a mower shaft having anopening associated therewith, said blade having resilient means forremovably engaging a margin of said opening.

9. A mower blade as in claim 8, wherein one end of said blade issharpened to provide a cutting edge and the other end of said blade isslotted endwise of the blade to form a pair of fingers constituting saidresilient means.

10. A mower blade adapted to be connected to a lug on a mower shaft,said blade having resilient means adapted to removably engage a marginof an opening in said lug, said resilient means being bifurcated to forma pair of parallel compressible fingers each having a notch in the outeredge thereof for engagement with said margin of said opening in saidlug.

11. The combination of claim 1, further comprising a shaft, a pluralityof said lugs mounted on said shaft in spaced relation to each other, aplurality of spacers mounted on said shaft between said lugs, said shafthaving at one end an abutment against which one of said spacers abuts,and a coil spring mounted on the other end of said shaft and abutting alug adjacent said other end to hold said lugs and spacers in assembledrelation on said shaft.

12. in a mower having a shaft, the combination of opposed lug memberslocated in the same plane and transverse to the axis of said shaft andadapted to be secured to said shaft and extending generally radiallytherefrom, and opposed blade members directly connected to said lugmembers, said blade members being movable on said lug members in a planeincluding the axis of said shaft.

13. In a mower, a lug adapted to be connected to a shaft of 5 the mowerand at its outer end to a blade of the mower, said lug being anelongated metal strip having a nomcircular opening at said outer end toreceive said blade, said opening having a long dimension and a shortdimension, said blade having connecting means which when compressed andturned so that the plane of the connecting means is aligned with saidlong dimension is insertable into said opening.

14. A mower blade as in claim 8, wherein said resilient means isbifurcated to form at least one displaceable finger for engagement withsaid margin of said opening.

15. A mower blade as in claim 8, wherein said resilient means isdisplaceable from a normal position to a second position to permitinstallation of said blade on and removal of said blade from said shaftand springing back to substantially said normal position to retain saidblade on said shaft.

16. The mower blade of claim 11, wherein one end of said blade issharpened to provide a cutting edge and the other end of said blade isslotted endwise of the blade to form said fingets.

17. The mower blade of claim 11, wherein said fingers when in theirnormal position, are wider than the opening, said fingers beingcompressible toward each other to a width smaller than the opening forinsertion into the opening.

zg gg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,678,668 D d July 25 1972 Inventofls) CARL W. MOTT It is certified thaterror appears in the aboveidentified patent and that said Letters Patentare hereby corrected as shown below: 1

Col. 1, line 8, "2955" should read --l;955-. C01. 2, lines 13 and 14,"one One" should read ---On one--. Col. 2, line is, "other" should read--outer. Col. 2, line 32, insert a per od after "maintained". C01. 3,line 64, "cocked turned or slightly should read turned or cockedslightly.

Signed and sealed this 1st day of May 1973.

(SEAL) Attest:

EDZIARD M. FLETCHER, J'E. ROBERT GOTTSCHALK Attesting OfficerCommissioner of Patents

1. In a mower having a shaft, the combination of a lug member adapted tobe secured to said shaft and extending generally radially therefrom, anda blade member, one of said members having means resilientlydisplaceable for removably engaging with the other of said members toconnect said members.
 2. The combination of claim 1, wherein saidresiliently displaceable means comprises a pair of fingers on one ofsaid members, the other of said members having an opening to removablyreceive said fingers.
 3. The combination of claim 2, wherein saidopening is non-circular and has a long and a short dimension, said shortdimension being transverse to a radius of said shaft, and said longdimension being generally parallel to said radius.
 4. The combination ofclaim 3, wherein said opening is pear-shaped.
 5. The combination ofclaim 2, wherein said fingers are formed on said blade, and said openingis formed in said lug.
 6. The combination of claim 2, wherein at leastone of said fingers has a notch for engaging the margin of said opening.7. The combination of claim 2, wherein said opening is smaller than thewidth of said fingers when in their normal position, said fingers beingcompressible toward each other for insertion into said opening, each ofsaid fingers having a notch in its outer edge for engaging the margin ofsaid opening when said fingers are inserted in said opening and arereleased from compression.
 8. A mower blade adapted to be connected to amower shaft having an opening associated therewith, said blade havingresilient means for removably engaging a margin of said opening.
 9. Amower blade as in claim 8, wherein one end of said blade is sharpened toprovide a cutting edge and the other end of said blade is slottedendwise of the blade to form a pair of fingers constituting saidresilient means.
 10. A mower blade adapted to be connected to a lug on amower shaft, said blade having resilient means adapted to removablyengage a margin of an opening in said lug, said resilient means beingbifurcated to form a pair of parallel compressible fingers each having anotch in the outer edge thereof for engagement with said margin of saidopening in said lug.
 11. The combination of claim 1, further comprisinga shaft, a plurality of said lugs mounted on said shaft in spacedrelation to each other, a plurality of spacers mounted on said shaftbetween said lugs, said shaft having at one end an abutment againstwhich one of said spacers abuts, and a coil spring mounted on the otherend of said shaft and abutting a lug adjacent said other end to holdsaid lugs and spacers in assembled relation on said shaft.
 12. In amower having a shaft, the combination of opposed lug members located inthe same plane and transverse to the axis of said shaft and adapted tobe secured to said shaft and extending generally radially therefrom, andopposed blade members directly connected to said lug members, said blademembers being movable on said lug members in a plane including the axisof said shaft.
 13. In a mower, a lug adapted to be connected to a shaftof the mower and at its outer end to a blade of the mower, said lugbeing an elongated metal strip having a non-circular opening at saidouter end to receive said blade, said opening having a long dimensionand a short dimension, said blade having connecting means which whencompressed and turned so that the plane of the connecting means isaligned with said long dimension is insertable into said opening.
 14. Amower blade as in claim 8, wherein said resilient means is bifurcated toform at least one displaceable finger for engagement with said margin ofsaid opening.
 15. A mower blade as in claim 8, wherein said resilientmeans is displaceable from a normal position to a second position topermit installation of said blade on and removal of said blade from saidshaft and springing back to substantially said normal position to retainsaid blade on said shaft.
 16. The mower blade of claim 11, wherein oneend of said blade is sharpened to provide a cutting edge and the otherend of said blade is slotted endwise of the blade to form said fingers.17. The mower blade of claim 11, wherein said fingers when in theirnormal position, are wider than the opening, said fingers beingcompressible toward each other to a width smaller than the opening forinsertion into the opening.